Pre heat oven to 180°c (356°f) bake and grease a 20cm cake tin
Warm syrup and milk, then stir in baking soda
Cream butter and soft brown sugar, beat in egg, then add milk mixture and dry ingredients alternately
Pour mixture into a 20cm cake tin
Bake for 45 minutes until cooked in the centre when tested with a skewer
While the cake is baking mix together crumb ingredients in a small saucepan over a medium low heat till boiling and most of the water has been removed
Transfer to a small bowl and allow to cook and then break into small chunks and set aside
Just before cake is ready bring the soft brown sugar, butter to the boil and boil for 1 minute, stirring. Add enough icing sugar to make it a thick, but runny consistency
Place cake on a cooling rack and place on plate and poor icing over slightly cooled cake so covers cake and sprinkle crumb over top of cake
Enjoy!